Sania Mirza [Images] and her American partner Christina Fusano advanced to the quarter-finals of US $175,000 Japan [Images] Open after a straight sets victory over the Polish-Romanian pair of Ursula Radwansaka and Agnes Szatmari in Tokyo on Tuesday.

Sania and Fusano won 6-3, 6-2.

The Indo-American pair will now take on the winner of the first round match between the Spanish duo of Arantxi Parra Santonja-Lourdes Dominguez Lino and the Colombian-American combine of Catalina Castano and Abigail Spears.

Sania had earlier won her singles opener against local wildcard Ayumi Morita. The second seeded Indian is up against Australian Casey Dell'Acqua in the second round.

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